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Course 23 · Lesson 5.1

The anatomy of an argument: claim, evidence, assumption and conclusion

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Lessons in this course

Course 23 outline

Module 1: How Research Works

  1. What research is and what a scholarly paper is for
  2. From topic to question: writing a research question that can be answered
  3. The working thesis and how it changes as research develops
  4. Taking notes, recording sources and organizing a project
  5. Academic integrity: quotation, paraphrase and plagiarism

Module 2: Primary and Secondary Sources

  1. Primary and secondary sources in theology and church history
  2. Source criticism: author, date, audience, purpose and transmission
  3. Translations, editions and the problem of reading ancient texts in English
  4. Judging the reliability of a source, including websites and popular books

Module 3: Finding and Reading Scholarship

  1. How peer review works and what it does not guarantee
  2. Finding articles, books and reference works with free and library tools
  3. Reading a scholarly work efficiently and critically
  4. Writing a literature review: summarizing a debate

Module 4: Citation

  1. Chicago notes and bibliography: books, articles and chapters
  2. Citing the Fathers, councils, creeds and online sources
  3. Biblical citation conventions: books, abbreviations, versions and numbering
  4. Managing a bibliography and checking citations

Module 5: Evaluating Arguments and Bias

  1. The anatomy of an argument: claim, evidence, assumption and conclusion
  2. Common fallacies and weak arguments in theological writing
  3. Identifying bias in sources: confessional, ideological and commercial
  4. Confirmation bias in your own work, and ways to reduce it

Module 6: Constructing Arguments and Writing

  1. Building a theological argument from Scripture, tradition and reason
  2. Outlining and drafting a research paper
  3. Clear analytical prose: paragraphs, transitions and plain language
  4. Revising, editing and checking quotations and facts

All courses

Program / Course 23: Research Methodology / Lesson 5.1

What you will learn

  • Identify the claim, reasons, evidence, assumptions and conclusion in a short argument.
  • Distinguish deductive from inductive and cumulative arguments.
  • Find unstated assumptions and ask whether they are reasonable.
  • Restate an argument fairly and judge how strongly its conclusion follows.

The big idea

An argument, in the scholarly sense, is a conclusion supported by reasons. To evaluate one, take it apart. What is the main claim? What reasons and evidence are offered for it? What must be assumed for those reasons to lead to the conclusion? Are there alternative explanations, and does the conclusion go further than the evidence allows? An argument can be valid in form and still rest on a doubtful premise, or have true premises and a weak link to the conclusion. Taking it apart shows which.

Key terms

Claim
A statement that something is true, which the author wants the reader to accept.
Premise
A statement offered as a reason for a conclusion.
Conclusion
The claim that the premises are meant to support.
Evidence
Facts, texts, testimony or observations offered to support a premise.
Assumption
A premise that an argument relies on but does not state or defend.
Deductive argument
An argument meant to show that the conclusion must be true if the premises are true.
Inductive argument
An argument meant to show that the conclusion is probable on the evidence, not certain.
Cumulative case
An argument made of many separate considerations that together support a conclusion, though none alone proves it.

Background

The word argument has two meanings in daily speech: a quarrel, and a reasoned case. Scholarship uses the second. A scholarly argument is a chain of reasons leading to a conclusion, and its purpose is to show the reader why the conclusion should be accepted. Philosophers and logicians have studied the structure of arguments since Aristotle, and Christian theologians from the early centuries onward used such reasoning, whether in the Fathers’ replies to heresies or in the scholastic method of the medieval universities.

Arguments come in kinds. In a deductive argument the conclusion follows necessarily: all humans are mortal, Socrates is human, so Socrates is mortal. Most arguments in history and theology, however, are inductive or cumulative. They argue that a conclusion is the best explanation of the evidence, or that several lines of evidence point the same way. This is normal and respectable. The right question to ask of such an argument is not ‘Is it proved?’ but ‘How strong is the support, and what are the alternatives?’

Many arguments also leave things unsaid. An author may state that a text uses a certain word and conclude that the author held a certain doctrine, without stating the assumption that the word carried that doctrinal sense at the time. Bringing these hidden steps into view is one of the most useful skills of a critical reader, and one of the most useful checks on your own writing. The apostle Paul tells his readers to test everything and hold fast to what is good (1 Thessalonians 5:21), and testing begins with seeing clearly what is being claimed.

Step-by-step explanation

Step 1: Find the conclusion

Ask what the author wants you to believe at the end. Look in the introduction and conclusion, and for words that signal one, such as ‘therefore’, ‘thus’, ‘it follows that’ and ‘this shows’. State the conclusion in one sentence.

If you cannot find a conclusion, the piece may be description, not argument. That is not a fault, but you should know which you are reading.

Step 2: List the reasons and the evidence

Ask why the author thinks the conclusion is true. Look for words such as ‘because’, ‘since’ and ‘for’. List each reason, and under it the evidence given: texts, dates, statistics, testimony, comparison. Note the page where each appears.

A reason without evidence is only an assertion. Mark those places for further checking.

Step 3: Find the assumptions

For each step from reason to conclusion, ask what must also be true for the step to work. If the reason is that a letter uses a term, and the conclusion is that the author taught a certain doctrine, the assumption is that the term meant this at the time. Write the assumption out.

Then ask whether it is reasonable, whether the author defends it, and what would follow if it were false. Some assumptions are shared and harmless. Others carry the whole argument.

Step 4: Consider alternatives

Ask what else might explain the evidence. If a text repeats phrases from an earlier text, the author may have copied it, or both may draw on a common source or a common liturgy. Has the author considered these? Do they weaken the conclusion, or does the author reply to them?

A good argument anticipates objections. A weak one ignores them. Notice which.

Step 5: Judge the strength, and restate the argument

Decide how strongly the conclusion follows from the support: certain, probable, plausible, possible or unsupported. Say which part is strongest and which weakest. Check whether the conclusion goes further than the evidence reaches, for instance by stating a possibility as a fact.

Finally, write the argument in a short form that the author would accept: ‘The author argues that X, because A and B, assuming C.’ If you can do this fairly, you are ready to criticize it.

  1. What exactly is the conclusion?
  2. What reasons are given, and what evidence supports each?
  3. What must be assumed for the reasons to support the conclusion?
  4. What alternative explanations could fit the same evidence?
  5. Does the conclusion claim more than the evidence shows?
  6. Could I restate the argument so that its author would agree?

Examples

A simple argument taken apart

Argument: ‘The letter must be late, since it speaks of a developed church order, and church order developed slowly.’ Conclusion: the letter is late. Reason: it speaks of developed church order. Assumption: church order developed slowly and uniformly, so a developed order cannot appear early. Question: was development uniform in all places? (A constructed example.)

A cumulative case

A historian argues that a text was written in a certain region from its dialect, its references to local customs and the earliest places it is quoted. No single clue is decisive, but together they make the conclusion probable. The reader should ask whether each clue is sound and whether they are independent. (A constructed example.)

A hidden assumption

A writer says that because a Father used the word ‘sacrifice’ for the Eucharist, he believed what a later council taught. The step assumes that the word meant the same to the Father as to the council. The assumption must be examined with the Father’s other uses and his context. (A constructed example.)

Different perspectives

Catholic

The scholastic tradition developed careful arguments in which the objections are stated first. Thomas Aquinas’s Summa Theologiae is the best known example: each question lists objections, offers a statement of the author’s view with reasons, and replies to each objection. Catholic thinkers also distinguish arguments from reason from truths received by faith, while holding that the two do not contradict.

Orthodox

Orthodox theology often argues from the witness of the Fathers, the councils and the liturgy, and tends to caution about reducing the mystery of God to a chain of logical steps. Orthodox writers use argument, as the Cappadocian Fathers did, and also stress prayer and experience as ways of knowing. A fair analysis notes the kind of argument being used.

Protestant

Protestants have often argued from Scripture through exegesis and from reason, with the Reformers using the tools of humanist scholarship. Reformed scholasticism developed formal arguments in the seventeenth century. Some Protestants prefer to emphasize testimony and experience. In each case the structure of the argument can be examined.

Philosophy and logic

Modern logicians distinguish validity, where a conclusion follows from the premises, from soundness, where the argument is valid and the premises are true. They also study informal reasoning, where arguments are judged by plausibility and strength. The Stanford Encyclopedia of Philosophy article on fallacies, in the library, gives a standard overview.

Why it matters

Almost everything that is written in theology, history and religion is an argument of some kind, whether it presents itself so or not. Learning to see its parts lets you read without being carried along, and write without hiding the weak points of your own case. It also makes disagreement more useful, since two people who disagree can say exactly which premise or assumption they dispute.

Common misunderstandings

Misunderstanding: An argument is only valid if it is deductive.

Correction: Most historical and theological arguments are inductive or cumulative. They can be strong or weak but are not simply valid or invalid. Judge them by how well the evidence supports the conclusion.

Misunderstanding: If I disagree with the conclusion, the argument must be bad.

Correction: Separate the conclusion from the reasoning. A good argument can have a conclusion you reject, in which case you must find the premise or assumption you dispute. A poor argument can reach a true conclusion.

Misunderstanding: Hidden assumptions are always a sign of dishonesty.

Correction: Every argument has unstated assumptions, most of them harmless. The task is to find the ones that carry weight and ask whether they are justified.

Misunderstanding: A longer list of evidence always makes a stronger argument.

Correction: Quality matters more than quantity. Ten weak points may be less convincing than one strong one, and repeated evidence may come from a single source.

Knowledge check

What are the parts of an argument?

A conclusion, which is the claim the author wants accepted, and premises or reasons offered for it. The reasons rest on evidence, such as texts and facts, and on assumptions that may be unstated. A full analysis also considers alternatives and objections. Finding each part lets the reader judge how well the conclusion is supported.

What is the difference between a deductive and an inductive argument?

A deductive argument aims to show that the conclusion must be true if the premises are. An inductive argument aims to show that the conclusion is probable on the evidence. Most arguments in history and theology are inductive or cumulative, and should be judged by the strength of support and the consideration of alternatives.

What is an unstated assumption, and why look for it?

An unstated assumption is a claim the argument needs but does not state or defend. For example, concluding that an author held a doctrine because he used a word assumes the word carried that sense. Finding assumptions reveals where an argument is vulnerable and where it needs support.

How do you judge whether a conclusion goes beyond the evidence?

Compare the strength of the conclusion with the strength of the support. If the evidence shows that something is possible and the author says it is certain, the conclusion goes too far. Check for alternative explanations that the author ignores, and look at the language of certainty used.

Think it through

  1. Take an argument you recently heard in a sermon, lecture or article. What was its conclusion, and what did it assume?
  2. Which assumptions do you rarely question in your own reasoning?
  3. Why might a scholar of another tradition find an assumption doubtful that you find obvious?
  4. How does stating the objections first, as Aquinas did, change the way a person argues?

Independent assignment

Taking an argument apart

In your own notebook, choose a short passage (one to three pages) of a scholarly work on your topic. Write about 400 words that identify its conclusion, reasons, evidence and at least two assumptions, name at least one alternative explanation, and judge the strength of the argument. Then restate it in two sentences that its author would accept. Do not send this to anyone.

Further study